• Proceedings of the KIEE Conference
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• 1997.07c
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• pp.1038-1040
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• 1997

This paper describes dynamic characteristics test of distance relay and current differential relay using Real Time Digital Simulator on double circuit transmission line. First, The double circuit T/L modeling on RTDS was proposed and the results from the proposed model were compared with those of PSS/E. This comparison shows the possibility of dynamic test using the RTDS. The relay included about 20 test items which are apt to include maloperation of protective relays in critical situations.

• KIEE International Transactions on Electrophysics and Applications
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• v.3C no.5
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• pp.194-198
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• 2003

A wide-band E-plane notch phased array antenna having bandwidths of 3:1 and a scan volume of $\pm$ 45 is designed considering the active element pattern (AEP) with analysis of the full structure of E-plane notch phased array antenna. Using the numerical E-plane waveguide simulator as an infinite linear array in the broadside angle, the active reflection coefficient (ARC) of the unit element is optimized in the design frequency range. To evaluate the convergence of the AEP, the simulation of full array as changing the number array is investigated, and the minimum numbers of array that have characteristics similar to the AEP of an infinite array are determined.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2017.11a
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• pp.190-191
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• 2017

본 연구는 산림 공간에서 산불소화시설인 수관수막타워의 방수시간에 따른 화재에 미치는 영향을 FDS(Fire Dynamics Simulator, 화재시뮬레이션)로 비교하였다. 본 연구를 진행하기 위한 기본 조건은 수관수막타워 높이 20m, 방수길이 40m, 방수량 400Lpm으로 해석공간 상에 수막타워를 3기 설치하였다. 수관수막타워 작동 초반 화재온도 $668.5^{\circ}C$에서 작동 450초 후 $145.6^{\circ}C$으로 감소되는 효과를 볼 수 있다. 이는 '산불소화시설 설치 및 운영 관리 지침'의 제3조 11절 6항의 '수관수막설비는 산불 접근 예상시간보다 10분전에 가동되도록 해야 한다.'의 타당성을 마련할 수 있다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39A no.9
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• pp.548-556
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• 2014

To cope with recently increasing demand for data traffics, heterogeneous networks have been actively studied, where small cells are deployed within a macro cell coverage with the same frequency band. To mitigate the interference from the macro cell to small cells, an enhanced Inter-cell Interference Coordination (eICIC) technique has been proposed, where ABS (Almost Blank Subframe) is used in time domain. However, there is a waste of resource since no data is transmitted in a macro-cell in ABS. In this paper, we propose a new interference management method by using a 3D sector beam based on Active Antenna System (AAS), where Genetic Algorithm (GA) is applied to reduce the antenna gain toward a small-cell. With the proposed scheme, the macro-cell and small cells can transmit data at the same time with the AAS antenna pattern generating reduced interference to small cells. The performance of the proposed scheme is evaluated by using an LTE-Advanced system level simulator.

• Korean Journal of Oriental Medicine
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• v.17 no.3
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• pp.77-85
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• 2011

Objectives : The purpose of this study was to develop a simulator which can analyze the anti-inflammatory effects of medical herbs based on e-cell concerning p38 MAPK signal pathway. Methods : We collected data concerning medical herbs with anti-inflammatory effects and the active compounds to provide as a fundamental databse and to validate the newly developed algorithm. At this time, we used the target database as pubmed and gathered the data by data mining tool, pathway studio. Also we have developed the web-based search system for confirming database related to anti-inflammation. We researched the mechanism of actions of proteins in p38 MAPK signal pathway when active compound has been inserted into the network. We reduced total network into TAK-MKK3-p38 and made the two types of mathematical model about active compounds' interaction. Results & Conclusion : We constructed the database which have 69 cases of medical herbs, 71 cases of active compounds, about 8,000 cases of URL(Uniform Resource Locator) related to papers and reports. We designed the ordinary differential equations for response of TAK, MKK3, p38 in e-cell's cytosol and nucleus. We used this formular as measure whether an active compound of medicinal plants which is inputted by an user would have an anti-inflammation effects. We developed the visualization program which could show the change of concentration over time.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.528-532
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• 2005

As the current IEEE 802.11 wireless LAN standard provides the unified channel access procedure for each traffic service without considering its own traffic characteristics, it is difficult to get its differentiated service qualities at IEEE 802.11 wireless LAN system. To solve this limit, IEEE 802.11e standard that can provide differentiated service to each traffic is under preparation. In this study, we implemented IEEE 802.11e EDCA channel access scheme with NS-2 simulator, and showed its numerical results in various system environments with using average delay and throughput as performance measures.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11a
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• pp.361-363
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• 2005

최근의 컴퓨터 네트워킹 환경에서 무선 멀티미디어 응용 서비스에 대한 사용자의 요구는 날로 증가하고 있다. 그러므로 사용자에게 원활한 서비스를 제공위해서 QoS 보장을 위한 무선 네트워크 프로토콜의 설계는 중요하다. 본 논문에서는 무선 인터넷에서 QoS를 보장하기 위한 표준인 IEEE 802.11e[1]의 문제점들을 분석하고, Multi-Hop Ad Hoc Network에서 성능 향상을 위하여 Single-channel Jamming 신호를 기반으로 한 SJMAC(Sing1e-channel Jamming MAC) 프로토콜을 설계하고, NS2 모듈을 구현한 후에 성능 평가를 하였다. 기존 IEEE 802.11e과의 성능 비교를 위하여 NS2 (Network Simulator2)[2]에 SJMAC 모듈을 추가하여 제안된 프로토콜의 성능을 검증한다.

• Proceedings of the IEEK Conference
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• 2004.06b
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• pp.359-362
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• 2004

Electron beam on high energy acceleration, which travels deeply and sharply through photoresist, became to be used in e-beam lithography apparatus for nano-patterning in due to its high resolution. An advanced electron beam lithography simulation tool is currently undergoing development for nano-patterning. This paper will demonstrate such simulation efforts with experiments at 200 keV e-beam lithography processes on PMMA, ZEP520 of which photoresist parameters and characteristics will be explained with simulation results. Neureuther parameters was extracted from the contrast curve of the resist

• Journal of Communications and Networks
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• v.11 no.1
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• pp.36-41
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• 2009

The IEEE 802.16 wireless metropolitan area network (WMAN) standard is designed to correct expensive communication costs in CDMA-based mobile communication systems and limited coverage problems in wireless LAN systems. Thus, the IEEE 802.16e standard can provide mobile high-speed packet access between mobile stations and the Internet service provider through the base station with cheap communication fees. To efficiently accommodate voice over IP (VoIP) services in IEEE 802.16 systems, an uplink quality of service packet-scheduling scheme is proposed, and its performance is evaluated with an NS-2 network simulator in this paper. Numerical results show that this proposed scheme can increase the system capacity by 100% more than in the unsolicited rand service (UGS) scheme and 30% more than the extended real-time polling service (ertPS) scheme, respectively.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2003.08a
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• pp.164-169
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• 2003

The need fur higher grid resolution in climate models is often discussed (e.g. McAvaney et al.,2001) because a number of important oceanic processes are not resolved by the current generation of coupled models, e.g., boundary currents, mesoscale eddy fluxes, sill through flows. McClean et al., (1997) and Bryan and Smith (1998) have compared simulated mesoscale variability in simulations at several eddy-resolving resolutions to TOPEX/Poseidon and similar data. (omitted)